Performance is very important in automation scenarios. Often, scripts and cmdlets work with more than a few objects and connect to more than a few remote systems to collect data.
The performance of the pipeline, especially when working with the Where-Object cmdlet, can be impacted heavily. In many cases, this is not necessary and can be corrected with very few, simple modifications to your code.
This recipe demonstrates the importance of filters when accessing the filesystem, as well as the Windows event log.